The loss of an eye or the total loss of sight of one eye may be secondary to a multitude of causes and continues to be a frequent occurrence with our troops during battle, despite the use of protective eyewear. The sudden loss of sight in one eye or the loss of an eye often necessitates immediate and extensive medical and psychological intervention. This loss will result in the patient’s sudden experience of the loss of depth perception, decrease of his or her visual field, and most frequently, depression. When compared with the other rehabilitation services in place for injuries resulting in systemic physical disabilities secondary to trauma, such as the loss of a limb, vision rehabilitation for the loss of depth perception and decrease in peripheral visual field is frequently not addressed at the initial or latter stage of these rehabilitation services.1
The annual incidence of enucleation is 4.3 per 100,000.2,3 Although it has been estimated that 50,000 patients lose a sighted eye each year, the annual incidence of acquired monocular vision is probably much higher because any patient who has no light perception in one eye is monocularly blind.2,4 Currently, low-vision rehabilitation programs are available for the partially sighted, such as those experiencing macular degeneration, but they do not readily meet the needs of the acquired monocular patient. Patients who become blind in one eye as the result of glaucoma, optic neuropathies, proliferative diabetic retinopathy, intraocular tumors, expulsive choroidal hemorrhage, endophthalmitis, and chronic uveitis could all be considered to have acquired monocular vision if their other eye functions relatively well.2 The purpose of this article is to illustrate the potential for monocular vision rehabilitation and justify adding monocular rehabilitation therapy to current vision rehabilitation programs and encourage future clinical case studies to measure functional outcomes.
The Buffalo Veterans Affairs (VA) Medical Center was selected by VA Central Office for the Continuum of Care Vision Impairment Services for Outpatient Services (VISOR) clinic. At Buffalo, senior leadership made the decision to place this new program, which includes optometric low-vision evaluations, low-vision therapy, home low-vision rehabilitation, and orientation and mobility (O&M) services, within the Department of Physical Medicine and Rehabilitation. An important aspect of the program design was to include coordination of low-vision optometrists, ophthalmologists, physiatrists, blind rehabilitation specialists (a.k.a. vision rehabilitation therapists), O&M instructors, and occupational therapists with vision rehabilitation. With the creation and development of this team approach within the Buffalo VA, the result has been the efficient provision of clinical vision rehabilitation services by enhancing integration for low-vision patients, monocular patients, and patients with traumatic brain injury.
The Acquired Monocular Vision Rehabilitation (AMVR) program was developed to guide and teach specific skills to each monocular patient.1 The development of this program was inspired by the study of the functional impact of acquired monocular vision from the patient’s perspective by Coday and colleagues.2 Of the 65 respondents to their study, 91% stated they had no formal training to help adapt to their sudden loss.2 In addition, most respondents believed that help adjusting to the loss of depth perception, safety and social concerns, and supportive counseling would have been beneficial.2
The data of Coday and colleagues2 broke down various aspects that were most difficult for patients to adjust to. They found that 39% noted cosmetic appearance was most difficult; 31% psychological impact; 22% ability to perform sports; and 11% ability to work.2
Their data also noted the percentage of patients reporting changes after monocular visual loss: 50% noted sports/hobbies; 40% social impact; 39% driving status; 39% mobility—steps/curbs; 23% employment status; 19% reading; and 11% watching television.2
Specifically, the social impact of visual loss revealed that many patients’ responses included self-reported depression, a need for professional counseling, loss of self-esteem, and decreased participation in social events.2
The timing of visual loss was an important factor in how quickly patients reported adapting to monocular vision. The study by Coday et al.2 found that patients with sudden visual loss (e.g., trauma) will generally adapt to a new level of function more slowly than those patients with gradual visual loss (e.g., glaucoma). They also noted that it was possible that formal training in adapting to a lack of depth perception and decreased visual field may expedite the learning process and improve function more rapidly.2
As a result, the AMVR program was organized with the goal to maximize the person’s remaining monocular vision; to teach visual skills; to acquire and to maintain independence, living, and functioning; and prevent depression.1
The 12 Appendices refer to details of evaluation and survey forms, questionnaires, questionnaire results, and test procedures that were used or were relevant to the procedures and Methods used in this case report. Those Appendices are available in the online supplementary digital content associated with this publication. The AMVR program1 includes an optometric monocular evaluation (see Appendix 1, available at http://links.lww.com/OPX/A114) and monocular vision rehabilitation therapy with a vision rehabilitation therapist. Specifically, the evaluation consists of a comprehensive history to include identifying goals and concerns, refraction with safety lenses, ocular health examination, and subsequent monocular ocular motility skills testing. After the evaluation, a vision rehabilitation assessment consists of home adaptive skills training to help patients cope with the obstacles they face when making the sudden transition to monocular vision. The goal of our service is to enhance each patient’s quality of life and ameliorate depression in patients who have suffered monocular vision loss. A scripted survey was designed because questionnaires used in other studies that assess functional visual loss were believed to be limited in scope with regard to assessing progress specific to monocular patients.
Monocular Visual Functioning Questionnaire
A scripted survey (see Appendix 2, available at http://links.lww.com/OPX/A114) was conducted preintervention and postintervention. The basis for the development of this survey was modeled after the VA Low Vision Visual Functioning Questionnaire (VA LV VFQ-48) by Stelmack et al.,5 which was developed to measure outcomes of low-vision rehabilitation. The results of the sensitivity study showed it to be a valid and reliable measure of changes that occur in visual ability as a result of vision rehabilitation.5 The VA LV VFQ-48 Questionnaire was not used because of its limited scope with regard to assessing monocular patients’ perspective of their problems instead of binocular vision loss. Modifications to the VA LV VFQ-48 were made by listing questions specific to monocular vision loss to create the Monocular Visual Functioning Questionnaire (MVFQ). The MVFQ was not validated through rigorous clinical research, as the VA LV VFQ-48, but designed for the purposes of monitoring any subjective changes preintervention and postintervention. This MVFQ is designed to be used with future monocular patients, with the plan to eventually report on its validity. Specifically, the MVFQ is a vision function questionnaire that captures the difficulty adults have performing daily activities who have lost one eye or have lost the sight in one eye. Response choices include not difficult, slightly/moderately difficult, extremely difficult, impossible, and do not do it for nonmonocular visual reasons (which is scored as missing data). This modified survey (MVFQ) contains 46 questions regarding various activities of daily living skills that are affected by a loss of depth perception and decreased visual field such as cooking, crossing the street, and driving by monitoring functional outcome changes in confidence, feelings of depression, and so on (see Appendix 2, available at http://links.lww.com/OPX/A114). This questionnaire is used to gather information on visual function both prerehabilization and postrehabilitation and is conducted by a vision rehabilitation therapist.
The following case report illustrates one example of concurrent vision rehabilitation team management of a later stage acquired monocular patient within a 1-year period (see Optometric Vision Rehabilitation Initial Evaluation–Appendix 1: Evaluation Template, available at http://links.lww.com/OPX/A114).
A 50-year-old man presented with a history of Bell palsy of his right eye 29 years earlier. The paralysis or weakness of facial nerve VII on the right side of his face caused complications from exposure keratopathy. Although tarsorrhaphy is viewed as a last alternative for many patients after other treatments have been attempted (e.g., patching, ointments, etc.), history revealed that nasal and lateral tarsorrhaphy was preformed, resulting in his right upper lid being sewn shut permanently. Consequently, the patient experienced acquired monocular vision 4 years before this evaluation. His last ophthalmological examination was 3 months before this evaluation. Follow-up ophthalmology care continues as recommended.
The physical examination began as the patient entered the examination room. His entry was observed as natural because he did not bump into the doorway. His personality was observed and noted as outgoing and alert.
Mobility issues were discussed that revealed he walked alone with moderate difficulty. Specifically, steps, stairs, and curbs were described as moderately difficult to maneuver. He revealed frustration when bumping into people and cutting people off frequently while walking, rating both as severe. He described driving as moderately difficult and chooses to seek other means of transportation because he is uncomfortable to drive because of loss of visual field. He also described that his psychological reaction to the loss of sight of one eye is difficult overall.
Distance vision was addressed, which he revealed not having difficulty watching television and that glare slightly bothered him. He reported that solid amber tinted prescription lenses, along with a baseball cap, were sufficient for glare reduction. He also reported having a transition progressive bifocal prescription at home. He preferred to wear his dark tinted prescription lenses because he is continued to be uncomfortable with the appearance of his lid being sewn closed.
For near vision, he used his progressive bifocal glasses at home only because they are not tinted. Other questions revealed severe fatigue while reading, moderate difficulty with losing his place while reading, and severe difficulty pouring liquids. He described spills occur frequently.
He was unemployed and noted that his ability to work remained severely difficult.
His hobbies included playing chess with moderate difficulty. His ability to perform sports overall was noted as severely difficult. He rode a bicycle and revealed he stopped playing basketball because he kept running into people and falling.
His main goal was expressed during this evaluation to walk safely at home and in the community.
Unaided visual acuity (distance and near):
* OD: lid is stitched shut
* OS: 20/40-1, 0.6M
Psychiatric: mood and affect: depression
Confrontation peripheral field: OS no peripheral restriction in all quadrants
Retinoscopy and subjective refraction final results:
* OD Balance
* OS –0.25 –2.25 × 045; VA 20/20; add +1.50; VA RS20
For safety, polycarbonate lenses were recommended. Therefore, a progressive bifocal prescription (OS only) in transition and polycarbonate was ordered and dispensed. A single-vision balance right lens was frosted to enhance a positive cosmetic appearance.
Other recommendations included completion of an MVFQ (preintervention) to monitor progress. Subsequent tests included ocular motility skills such as saccades and pursuits. Visual memory and motor free visual perceptual testing was also recommended. Monocular vision therapy was recommended to include mobility training using mirrors on his bicycle and walking cane to increase his visual field and enhance safety. A postintervention MVFQ was also conducted.
Monocular Visual Functioning Questionnaire
Results of the MVFQ (see Appendix 3, available at http://links.lww.com/OPX/A114) indicated that approximately 54% (24 of 46) of the tasks identified were identified as slightly/moderate difficult; that approximately 24% (11 of 46) of the tasks identified were extremely difficult; and that approximately 11% (5 of 46) of the tasks identified were impossible. Only approximately 11% of the tasks identified on the questionnaire were either not difficult (3 of 46) or not applicable (2 of 46) to being monocular (see Appendix 3, available at http://links.lww.com/OPX/A114).
Further testing results with the Computer Orthopter (VTS3) computer diagnostics regarding monocular saccades, pursuits, and visual memory were noted as accurate and/or acceptable (see Appendix 4, available at http://links.lww.com/OPX/A114).
The Motor Free Visual Perceptual Test was performed to measure higher level visual perceptual processing skills (e.g., visual closure, figure-ground discrimination, etc.; see Appendix 5, available at http://links.lww.com/OPX/A114). Results compared with same-age peers were scored at a percentile rank of 1%—significantly below an average performance percentile rank of 50%.
Vision Rehabilitation Therapist Assessment
After the optometric monocular vision rehabilitation evaluation, a vision rehabilitation therapist assessment was conducted and described the patient currently living with his brother and stated that he plans to get his own place.
Case management regarding public services was discussed but noted as not needed at this time. Cultural background information regarding traditions with family roles, customs, and so on, was not an issue pertaining to therapy. Pain was assessed, but the patient did not reveal any issues at this time.
Instructional Standard 1: Meal Management
Pouring was addressed and noted as difficult with the loss of depth perception. Various issues were discussed regarding the loss of depth perception, and devices were demonstrated.6–16 His stove and microwave dials will be observed and marked during a home visit if needed. He also benefited with the use a double spatula and bump dots. Adaptive device(s) were ordered.
Instructional Standard 2: Home Management
The use of his washing machine and dryer for laundry will be observed and marked during a home visit if needed.
Instructional Standard 3: Financial Management
No needs identified.
Instructional Standard 4: Family Care Management (Children or Incapacitated Adults)
No needs identified.
Instructional Standard 5: Communications
No needs identified.
Instructional Standard 6: Personal Care
He revealed having difficulty with oral/facial hygiene and grooming.
Instructional Standard 7: Leisure Time Activities
Patient stated that he loves playing sports—basketball, baseball, and so on. He states that he has issues with depth perception when he is playing sports, such as he is not shooting the basketball close enough to the basket and his sight of the baseball is not timed well enough to hit it, and so on. He also noted that he stopped playing games with his friends because of safety issues. He kept bumping into other players and falling because of his decrease in visual field. He noted feelings of depression with not playing games with his friends.
Instructional Standard 8: Job Site Adaptations
No needs identified.
Instructional Standard 9: Orientation and Mobility Assessment
Patient noted having a history of falling and travel concerns. He noted that he still has difficulty judging the last step when descending stairs.
Patient goals: to travel more safely in his environment.
Regarding residential travel, patient noted that he loves to ride his bicycle but states that he is afraid to do so now, with his vision loss.
Instructional Standard 10: Low-Vision Devices
Photosensitivity and glare issues were addressed.
Audiology was also not identified as an issue for this patient.
With regard to an adjustment issue, patient was asked, how has he adjusted to vision changes? Patient stated that he has been feeling depressed because of the fact that he does not feel that he can do as much as he used to do and cannot do it as easily.
Monocular Vision Rehabilitation Therapy
Therapy consisted of appointments scheduled with the patient in the clinic and five orientation and mobility visits scheduled on site at his residence. Telephone clinics were documented to monitor progress and answer any questions throughout the therapy process.
Instructional Standard 1: Meal Management
With his loss of depth perception, he benefited with the use of a liquid level indicator, as well as a small Dycem mat to provide contrast for depth location when reaching for his cup on the counter. With regard to cooking functions, such as chop/slice/spread/mix, he benefited with the use of a contrast cutting board, rocker knife, and Dycem mat for safer food preparation. He also benefited with the use of a food chopper.
A review of daily living activities indicated that the patient is still struggling with some cooking tasks. The patient will benefit from oven mitts that cover his forearms and low-vision measuring cups/spoons because the patient stated that it is harder now to judge the right amount of spices when sprinkled from the container. It was suggested that, in addition to using measuring utensils, the patient can sprinkle the spices into his hand first or onto a contrasted background such as a napkin or his contrast cutting board previously issued to him. Pouring, measuring, use of contrast, hand shake, and scanning techniques were reviewed with the patient.
Instructional Standard 6: Personal Care
Regarding oral/facial hygiene and grooming such as trimming his mustache and side burns evenly because he must see his image at an angle using two mirrors. The use of a 5× magnifying mirror and a standard mirror was demonstrated, enabling him to be able to see the image of his side burns from the angled magnifying mirror in the standard mirror. He currently used a safety razor, but the safety benefits of an electric razor were reviewed, resulting in more control while shaving. The electric razor also provides tactile cues for facial landmarks for grooming.
Instructional Standard 7: Leisure Time Activities
General routine tasks in the home and certain sport activities become more difficult because of the loss of depth perception and decrease in visual field. Accurately judging distances are extremely important for safety. As was noted in the assessment, he loves playing sports, such as basketball, baseball, and so on. He stated that he has issues with depth perception when he is playing. He noted that he is not shooting the basketball close enough to the basket, and that his sight of the baseball is not timed well enough to hit it.
He also noted that he stopped playing games with his friends because of safety issues. He kept bumping into other players and falling because of his decrease in visual field. He noted feelings of depression when he stopped playing games with his friends. The Wii gaming system is a safer leisure time activity (for basketball, baseball, etc.) with his friends because each player stands within their space, and both players are looking at the television screen without the need for binocular depth perception or binocular visual field.
Wii therapy is currently used in our outpatient clinic. The Wii gaming system improves eye-hand coordination and visual skills training. Wii Basketball and Wii Tennis teach adaptations to judging distances without depth perception. Wii Basketball is also safer than actual basketball because of quick changes in direction and decreased peripheral visual field.
This gaming system also benefits the patient by being able to safely play basketball and other sports with his friends and family because he has noted disappointment not being able to safely play conventional basketball.
For eye-hand coordination with the Wii game system, the patient demonstrated safe operation and handling of the Wii controls and obtained knowledge in using the controller for game navigation. Regular games were also introduced. He completed one round of baseball, golf, and bowling.
Patient was extremely pleased playing Wii sports as he is an athlete unable to engage safely in the sports as he once had because of his vision loss. The exercise routine will also benefit his overall health and well-being as he has very little other physical activities. The Wii system proved beneficial for this patient to improve his self-esteem, eye-hand coordination, judgment of depth and distance, scanning visual fields, and safety to engage in recreation and physical exercise that otherwise may pose a safety risk factor because of his impaired depth perception and reduced peripheral visual field. Patient was motivated and agreeable to follow the recommended treatment plan to use the Wii for home exercise.
In addition, health benefits of a routine exercise program with the Wii were discussed with the patient. He is a diabetic and states that his blood sugars fluctuate, and that he does not have an exercise regimen established. Our patient was advised to communicate with his primary care physician regarding diabetes management and his exercise program with the Wii. As this patient is monocular, it is especially important that risk factors for diabetic eye disease be minimized. Adherence to the Wii exercise program is felt to be a positive contribution to improved overall health, fitness, self-esteem, and visual skills.
Instructional Standard 9: Orientation and Mobility Assessment
Our patient was instructed on proper protective techniques (see Appendix 6, available at http://links.lww.com/OPX/A114) as he stated that he will run into a door frame sometimes. Patient also stated that he has difficulty going up and down stairs because of loss of depth perception. Judgment of the last step when descending stairs was demonstrated and discussed. It was suggested that he look for other visual cues, such as where the step adjoins the wall. He noted that using the railing and walking slowly were helpful. A support cane was recommended to detect the depth and width of steps and curbs. This was provided through physical therapy.
Education and training were provided regarding relative motion and perspective principles and strategies for monocular vision6–16 (see Appendices 7–9, available at http://links.lww.com/OPX/A114). Principles were instructed through Nerf ball toss, Nerf bat and ball toss, and pickup sticks.
Regarding residential travel, patient noted that he loves to ride his bicycle but states that he is afraid to do so now, with his vision loss. To increase his peripheral visual field, a mirror can be strategically placed to increase peripheral visual field without turning his head (see Appendix 10, available at http://links.lww.com/OPX/A114). A side mirror attached to his handlebars with Velcro, on the side of his vision loss (i.e., right handle bar) would allow him to view part of his right field without turning his head. A bicycle mirror was ordered and attached to his handle bar with Velcro (on his right side). Training was provided by our O&M instructor. As he rode his bicycle, he noted that the mirror helped increase his visual field and safety while riding.
A bicycle mirror attached with Velcro to a standard cane issued through physical therapy and held on his right side while walking will also enable him to view part of his right peripheral field without turning his head. See example (Appendix 11, available at http://links.lww.com/OPX/A114). This will enhance his mobility and safety especially at night. An attachable mirror was ordered, and training was provided by our O&M instructor. With the bicycle mirror attached to his support cane, he demonstrated the ability to use the mirror to spot things next to him and behind him. When standing facing forward, he was able to see his front door behind him, the bushes and porch next to him, and everything else around him. He greatly benefited from this because he was able to see things on his right side before he turned into them. For example, he was able to see that there was a line of bushes on his right that prevented him from making a quick right turn running into them. Subjectively, he was extremely pleased with the mirror. He stated being very happy that he “got peripheral vision back.”
Mirrors can also be beneficial for accessing peripheral visual field for other ocular conditions such as hemianopsias. Bicycle mirrors can be attached to standard canes, walkers, and wheelchairs. Each situation helps the patient access his or her peripheral vision by looking at the mirror with minimal head movement. See example (Appendix 11, available at http://links.lww.com/OPX/A114).
Instructional Standard 10: Low-Vision Devices and Other Vision Issues
Patient was assessed with glare-reducing filters. He noted that the yellow-, orange-, and plum-colored filters helped reduce outdoor glare when he is walking and riding his bike. The filters were ordered and dispensed.
Eye safety was reviewed with the patient regarding the importance and necessity for eyewear to protect his “good” eye. Clear high-performance protective eyewear with a lightweight ballistic nylon frame was also recommended to be worn when he is not wearing sunglasses or reading glasses.
Patient stated that the glare on his cell phone is also troublesome to him. Consequently, an assortment of acetate sheets was demonstrated. The patient noted that yellow acetate filters reduced the glare on his cell phone. Several templates were cut to fit his cell phone and issued to the patient.
To encourage creative thinking and enhance visual perceptual skills, the Parquetry Blocks design book was reviewed with the patient. He reported doing exercises routinely.
Monocular Visual Functioning Questionnaire (Postintervention)
The MVFQ was readministered to the patient and compared with the initial questionnaire (see Appendix 12, available at http://links.lww.com/OPX/A114).
Results of the MVFQ noted approximately 63% (10 of 16) of the tasks that were noted as extremely difficult or impossible improved to slightly/moderate difficulty within less than 2 months of concurrent vision rehabilitation intervention. The patient noted experiencing an improved disposition in regard to his self-confidence, self-image, and ease at engaging in more social activities. He stated being more self-confident and feeling better about himself. He noted that he has been going out more often, including going out to dinner.
Psychosocial adjustment was assessed in which the patient stated that the vision therapy he received has been an “amazing experience.” He further stated that he was really struggling, and now, he is more optimistic. He expressed feeling a sense of hope, increased self-confidence, improved motor skills, and less depression since learning more about his condition and adaptations he can maintain. He stated that he feels he is a “better me.”
Although this was one case example, the patient’s positive feedback encourages further data to be collected with future monocular patients evaluated at an earlier stage of their vision loss and to continue to structure supportive services by demonstrating new adaptive techniques and exercises to show each person “is-able” and not “dis-abled.”
The limitation of this study is that low-vision optometrists do not regularly receive referrals for monocular patients. This one patient was referred for services because a case manager for the visually impaired was contacted by a behavior health clinician regarding this monocular patient and the concerns he was expressing regarding his visual condition. The case manager contacted the low-vision optometrist, and hence, the Monocular Vision Rehabilitation Evaluation and Therapy Program was recommended. Monocular patients may be expressing concerns, but they were most likely told “nothing can be done,” which is only partially true. This is similar to low-vision rehabilitation in that educating other doctors that although we cannot change the patient’s vision loss, rehabilitation therapy is available to help each patient adapt to the vision loss to remain independent and safe with the goal to prevent depression. Future studies of monocular patients are needed to quantify validity of rehabilitation intervention and functional outcomes at early and late stages of acquired monocular vision loss.
3495 Bailey Ave MC 117
Buffalo, NY 14215
e-mail: firstname.lastname@example.org; email@example.com
Received October 11, 2012; accepted November 26, 2012.
The Appendices are available online at http://links.lww.com/OPX/A114.
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